Message ID | 20250209111034.241571-6-ericwouds@gmail.com (mailing list archive) |
---|---|
State | Changes Requested |
Delegated to: | Netdev Maintainers |
Headers | show |
Series | bridge-fastpath and related improvements | expand |
On Sun, Feb 09, 2025 at 12:10:25PM +0100, Eric Woudstra wrote: > @@ -1453,7 +1454,10 @@ void br_vlan_fill_forward_path_pvid(struct net_bridge *br, > if (!br_opt_get(br, BROPT_VLAN_ENABLED)) > return; > > - vg = br_vlan_group(br); > + if (p) > + vg = nbp_vlan_group(p); > + else > + vg = br_vlan_group(br); > > if (idx >= 0 && > ctx->vlan[idx].proto == br->vlan_proto) { I think the original usage of br_vlan_group() here was incorrect, and so is the new usage of nbp_vlan_group(). They should be br_vlan_group_rcu() and nbp_vlan_group_rcu(). The lockdep annotation is important, otherwise I get this with CONFIG_PROVE_LOCKING=y: [ 1140.931869] ============================= [ 1140.935996] WARNING: suspicious RCU usage [ 1140.940094] 6.14.0-rc1-00224-gda8926a49ba1-dirty #2666 Not tainted [ 1140.946371] ----------------------------- [ 1140.950520] net/bridge/br_private.h:1604 suspicious rcu_dereference_protected() usage! [ 1140.958622] [ 1140.958622] other info that might help us debug this: [ 1140.958622] [ 1140.966752] [ 1140.966752] rcu_scheduler_active = 2, debug_locks = 1 [ 1140.973435] 2 locks held by swapper/0/0: [ 1140.977521] #0: ffffd9f646c333b0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x4/0x40 [ 1140.986404] #1: ffffd9f646c333b0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x4/0x48 [ 1140.995170] [ 1140.995170] stack backtrace: [ 1140.999636] CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.14.0-rc1-00224-gda8926a49ba1-dirty #2666 [ 1140.999650] Hardware name: LS1028A RDB Board (DT) [ 1140.999656] Call trace: [ 1140.999660] show_stack+0x24/0x38 (C) [ 1140.999683] dump_stack_lvl+0x40/0xa0 [ 1140.999698] dump_stack+0x18/0x24 [ 1140.999711] lockdep_rcu_suspicious+0x174/0x218 [ 1140.999723] br_vlan_fill_forward_path_pvid+0x90/0x150 [ 1140.999735] br_fill_forward_path+0x54/0x1b0 [ 1140.999751] dev_fill_bridge_path+0x9c/0x188 [ 1140.999766] nft_dev_fill_bridge_path+0x2ac/0x418 [ 1140.999785] nft_flow_offload_bridge_init+0x188/0x1c8 [ 1140.999801] nft_flow_offload_eval+0x18c/0x300 [ 1140.999816] nft_do_chain+0x1c8/0x538 [ 1140.999831] nft_do_chain_bridge+0x15c/0x210 [ 1140.999846] nf_hook_slow+0x80/0x130 [ 1140.999862] NF_HOOK+0xd8/0x1d0 [ 1140.999871] __br_forward+0x138/0x1a0 [ 1140.999880] br_forward+0xd8/0x160 [ 1140.999889] br_handle_frame_finish+0x3bc/0x5a8 [ 1140.999900] br_nf_pre_routing_finish+0x538/0x608 [ 1140.999917] NF_HOOK+0x254/0x298 [ 1140.999933] br_nf_pre_routing+0x3e8/0x428 [ 1140.999949] br_handle_frame+0x264/0x490 [ 1140.999959] __netif_receive_skb_core+0x13c/0x1128 [ 1140.999975] __netif_receive_skb_list_core+0xd4/0x1e8 [ 1140.999989] netif_receive_skb_list_internal+0x224/0x338 [ 1141.000000] napi_complete_done+0xb4/0x1d8 [ 1141.000012] gro_cell_poll+0x94/0xb8 [ 1141.000025] __napi_poll+0x58/0x258 [ 1141.000040] net_rx_action+0x1f4/0x3e0 [ 1141.000055] handle_softirqs+0x184/0x458 [ 1141.000070] __do_softirq+0x20/0x2c [ 1141.000079] ____do_softirq+0x1c/0x30 [ 1141.000095] call_on_irq_stack+0x24/0x58 [ 1141.000111] do_softirq_own_stack+0x28/0x40 [ 1141.000127] __irq_exit_rcu+0xd4/0x1a0 [ 1141.000139] irq_exit_rcu+0x1c/0x40 [ 1141.000152] el1_interrupt+0x8c/0xc0 [ 1141.000170] el1h_64_irq_handler+0x18/0x28 [ 1141.000186] el1h_64_irq+0x6c/0x70 [ 1141.000195] arch_local_irq_enable+0x8/0x10 (P) [ 1141.000213] cpuidle_enter+0x44/0x68 [ 1141.000228] do_idle+0x1e8/0x280 [ 1141.000238] cpu_startup_entry+0x40/0x50 [ 1141.000248] rest_init+0x1c4/0x1d0 [ 1141.000260] start_kernel+0x324/0x3e8 [ 1141.000272] __primary_switched+0x88/0x98 [ 1141.197568] ------------[ cut here ]------------
On 2/11/25 2:28 PM, Vladimir Oltean wrote: > On Sun, Feb 09, 2025 at 12:10:25PM +0100, Eric Woudstra wrote: >> @@ -1453,7 +1454,10 @@ void br_vlan_fill_forward_path_pvid(struct net_bridge *br, >> if (!br_opt_get(br, BROPT_VLAN_ENABLED)) >> return; >> >> - vg = br_vlan_group(br); >> + if (p) >> + vg = nbp_vlan_group(p); >> + else >> + vg = br_vlan_group(br); >> >> if (idx >= 0 && >> ctx->vlan[idx].proto == br->vlan_proto) { > > I think the original usage of br_vlan_group() here was incorrect, and so > is the new usage of nbp_vlan_group(). They should be br_vlan_group_rcu() > and nbp_vlan_group_rcu(). > > The lockdep annotation is important, otherwise I get this with CONFIG_PROVE_LOCKING=y: > [ 1140.931869] ============================= > [ 1140.935996] WARNING: suspicious RCU usage > [ 1140.940094] 6.14.0-rc1-00224-gda8926a49ba1-dirty #2666 Not tainted > [ 1140.946371] ----------------------------- > [ 1140.950520] net/bridge/br_private.h:1604 suspicious rcu_dereference_protected() usage! > [ 1140.958622] > [ 1140.958622] other info that might help us debug this: > [ 1140.958622] > [ 1140.966752] > [ 1140.966752] rcu_scheduler_active = 2, debug_locks = 1 > [ 1140.973435] 2 locks held by swapper/0/0: > [ 1140.977521] #0: ffffd9f646c333b0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x4/0x40 > [ 1140.986404] #1: ffffd9f646c333b0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x4/0x48 > [ 1140.995170] > [ 1140.995170] stack backtrace: > [ 1140.999636] CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.14.0-rc1-00224-gda8926a49ba1-dirty #2666 > [ 1140.999650] Hardware name: LS1028A RDB Board (DT) > [ 1140.999656] Call trace: > [ 1140.999660] show_stack+0x24/0x38 (C) > [ 1140.999683] dump_stack_lvl+0x40/0xa0 > [ 1140.999698] dump_stack+0x18/0x24 > [ 1140.999711] lockdep_rcu_suspicious+0x174/0x218 > [ 1140.999723] br_vlan_fill_forward_path_pvid+0x90/0x150 > [ 1140.999735] br_fill_forward_path+0x54/0x1b0 > [ 1140.999751] dev_fill_bridge_path+0x9c/0x188 > [ 1140.999766] nft_dev_fill_bridge_path+0x2ac/0x418 > [ 1140.999785] nft_flow_offload_bridge_init+0x188/0x1c8 > [ 1140.999801] nft_flow_offload_eval+0x18c/0x300 > [ 1140.999816] nft_do_chain+0x1c8/0x538 > [ 1140.999831] nft_do_chain_bridge+0x15c/0x210 > [ 1140.999846] nf_hook_slow+0x80/0x130 > [ 1140.999862] NF_HOOK+0xd8/0x1d0 > [ 1140.999871] __br_forward+0x138/0x1a0 > [ 1140.999880] br_forward+0xd8/0x160 > [ 1140.999889] br_handle_frame_finish+0x3bc/0x5a8 > [ 1140.999900] br_nf_pre_routing_finish+0x538/0x608 > [ 1140.999917] NF_HOOK+0x254/0x298 > [ 1140.999933] br_nf_pre_routing+0x3e8/0x428 > [ 1140.999949] br_handle_frame+0x264/0x490 > [ 1140.999959] __netif_receive_skb_core+0x13c/0x1128 > [ 1140.999975] __netif_receive_skb_list_core+0xd4/0x1e8 > [ 1140.999989] netif_receive_skb_list_internal+0x224/0x338 > [ 1141.000000] napi_complete_done+0xb4/0x1d8 > [ 1141.000012] gro_cell_poll+0x94/0xb8 > [ 1141.000025] __napi_poll+0x58/0x258 > [ 1141.000040] net_rx_action+0x1f4/0x3e0 > [ 1141.000055] handle_softirqs+0x184/0x458 > [ 1141.000070] __do_softirq+0x20/0x2c > [ 1141.000079] ____do_softirq+0x1c/0x30 > [ 1141.000095] call_on_irq_stack+0x24/0x58 > [ 1141.000111] do_softirq_own_stack+0x28/0x40 > [ 1141.000127] __irq_exit_rcu+0xd4/0x1a0 > [ 1141.000139] irq_exit_rcu+0x1c/0x40 > [ 1141.000152] el1_interrupt+0x8c/0xc0 > [ 1141.000170] el1h_64_irq_handler+0x18/0x28 > [ 1141.000186] el1h_64_irq+0x6c/0x70 > [ 1141.000195] arch_local_irq_enable+0x8/0x10 (P) > [ 1141.000213] cpuidle_enter+0x44/0x68 > [ 1141.000228] do_idle+0x1e8/0x280 > [ 1141.000238] cpu_startup_entry+0x40/0x50 > [ 1141.000248] rest_init+0x1c4/0x1d0 > [ 1141.000260] start_kernel+0x324/0x3e8 > [ 1141.000272] __primary_switched+0x88/0x98 > [ 1141.197568] ------------[ cut here ]------------ Thanks. I will correct both in v7.
On Tue, Feb 11, 2025 at 03:43:22PM +0100, Eric Woudstra wrote:
> Thanks. I will correct both in v7.
Please wait a bit more for v7. I'm trying really hard to ask a pertinent
question on patch 11/14, which currently I don't understand very well
what it does and why it is needed.
On 2/11/25 15:28, Vladimir Oltean wrote: > On Sun, Feb 09, 2025 at 12:10:25PM +0100, Eric Woudstra wrote: >> @@ -1453,7 +1454,10 @@ void br_vlan_fill_forward_path_pvid(struct net_bridge *br, >> if (!br_opt_get(br, BROPT_VLAN_ENABLED)) >> return; >> >> - vg = br_vlan_group(br); >> + if (p) >> + vg = nbp_vlan_group(p); >> + else >> + vg = br_vlan_group(br); >> >> if (idx >= 0 && >> ctx->vlan[idx].proto == br->vlan_proto) { > > I think the original usage of br_vlan_group() here was incorrect, and so > is the new usage of nbp_vlan_group(). They should be br_vlan_group_rcu() > and nbp_vlan_group_rcu(). > Oops, right. Nice catch!
On 2/11/25 5:00 PM, Nikolay Aleksandrov wrote: > On 2/11/25 15:28, Vladimir Oltean wrote: >> On Sun, Feb 09, 2025 at 12:10:25PM +0100, Eric Woudstra wrote: >>> @@ -1453,7 +1454,10 @@ void br_vlan_fill_forward_path_pvid(struct net_bridge *br, >>> if (!br_opt_get(br, BROPT_VLAN_ENABLED)) >>> return; >>> >>> - vg = br_vlan_group(br); >>> + if (p) >>> + vg = nbp_vlan_group(p); >>> + else >>> + vg = br_vlan_group(br); >>> >>> if (idx >= 0 && >>> ctx->vlan[idx].proto == br->vlan_proto) { >> >> I think the original usage of br_vlan_group() here was incorrect, and so >> is the new usage of nbp_vlan_group(). They should be br_vlan_group_rcu() >> and nbp_vlan_group_rcu(). >> > > Oops, right. Nice catch! > Hi Nikolay, I gather that I can include your Acked-by also in the corrected patch.
On 2/11/25 18:35, Eric Woudstra wrote: > > > On 2/11/25 5:00 PM, Nikolay Aleksandrov wrote: >> On 2/11/25 15:28, Vladimir Oltean wrote: >>> On Sun, Feb 09, 2025 at 12:10:25PM +0100, Eric Woudstra wrote: >>>> @@ -1453,7 +1454,10 @@ void br_vlan_fill_forward_path_pvid(struct net_bridge *br, >>>> if (!br_opt_get(br, BROPT_VLAN_ENABLED)) >>>> return; >>>> >>>> - vg = br_vlan_group(br); >>>> + if (p) >>>> + vg = nbp_vlan_group(p); >>>> + else >>>> + vg = br_vlan_group(br); >>>> >>>> if (idx >= 0 && >>>> ctx->vlan[idx].proto == br->vlan_proto) { >>> >>> I think the original usage of br_vlan_group() here was incorrect, and so >>> is the new usage of nbp_vlan_group(). They should be br_vlan_group_rcu() >>> and nbp_vlan_group_rcu(). >>> >> >> Oops, right. Nice catch! >> > > Hi Nikolay, > > I gather that I can include your Acked-by also in the corrected patch. > Yes, thanks.
diff --git a/net/bridge/br_device.c b/net/bridge/br_device.c index 0ab4613aa07a..c7646afc8b96 100644 --- a/net/bridge/br_device.c +++ b/net/bridge/br_device.c @@ -383,16 +383,25 @@ static int br_del_slave(struct net_device *dev, struct net_device *slave_dev) static int br_fill_forward_path(struct net_device_path_ctx *ctx, struct net_device_path *path) { + struct net_bridge_port *src, *dst; struct net_bridge_fdb_entry *f; - struct net_bridge_port *dst; struct net_bridge *br; - if (netif_is_bridge_port(ctx->dev)) - return -1; + if (netif_is_bridge_port(ctx->dev)) { + struct net_device *br_dev; + + br_dev = netdev_master_upper_dev_get_rcu((struct net_device *)ctx->dev); + if (!br_dev) + return -1; - br = netdev_priv(ctx->dev); + src = br_port_get_rcu(ctx->dev); + br = netdev_priv(br_dev); + } else { + src = NULL; + br = netdev_priv(ctx->dev); + } - br_vlan_fill_forward_path_pvid(br, ctx, path); + br_vlan_fill_forward_path_pvid(br, src, ctx, path); f = br_fdb_find_rcu(br, ctx->daddr, path->bridge.vlan_id); if (!f) diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h index 1054b8a88edc..a0b950390a16 100644 --- a/net/bridge/br_private.h +++ b/net/bridge/br_private.h @@ -1584,6 +1584,7 @@ bool br_vlan_can_enter_range(const struct net_bridge_vlan *v_curr, const struct net_bridge_vlan *range_end); void br_vlan_fill_forward_path_pvid(struct net_bridge *br, + struct net_bridge_port *p, struct net_device_path_ctx *ctx, struct net_device_path *path); int br_vlan_fill_forward_path_mode(struct net_bridge *br, @@ -1753,6 +1754,7 @@ static inline int nbp_get_num_vlan_infos(struct net_bridge_port *p, } static inline void br_vlan_fill_forward_path_pvid(struct net_bridge *br, + struct net_bridge_port *p, struct net_device_path_ctx *ctx, struct net_device_path *path) { diff --git a/net/bridge/br_vlan.c b/net/bridge/br_vlan.c index d9a69ec9affe..07dae3655c26 100644 --- a/net/bridge/br_vlan.c +++ b/net/bridge/br_vlan.c @@ -1441,6 +1441,7 @@ int br_vlan_get_pvid_rcu(const struct net_device *dev, u16 *p_pvid) EXPORT_SYMBOL_GPL(br_vlan_get_pvid_rcu); void br_vlan_fill_forward_path_pvid(struct net_bridge *br, + struct net_bridge_port *p, struct net_device_path_ctx *ctx, struct net_device_path *path) { @@ -1453,7 +1454,10 @@ void br_vlan_fill_forward_path_pvid(struct net_bridge *br, if (!br_opt_get(br, BROPT_VLAN_ENABLED)) return; - vg = br_vlan_group(br); + if (p) + vg = nbp_vlan_group(p); + else + vg = br_vlan_group(br); if (idx >= 0 && ctx->vlan[idx].proto == br->vlan_proto) {